Querying a whois db for url info: "created on"

It's common knowledge that spammers links lead to sites that are often only days or weeks old.

I would like to use an extension (like stopforumspam which queries the sfs db) that queries the URL tag of posts/signatures being edited via whois.de/"thedomainname" ;
if "created on" returns <1 month (or 3 or 6) then editing of post or signature is denied and added to a table (as do ext url checker and stopforumspam).

I saw 50 queries per hour and IP are allowed... maybe another for more queries would be a good idea.

Is it do-able? Or which whois db can be queried for such things in a automated fashion?